x86/amd_node: Fix PCI device reference counting in amd_smn_init()grafted

The local "root" pointer is a temporary variable used during the device
search. Therefore, refcount related to the search iterators should be cleaned
up after the search is complete.

Use the __free() cleanup macro to ensure the refcount is decremented when the
temporary pointer goes out of scope.

Additionally, increment the refcount when caching a root pointer. This ensures
the in-use refcount is separate from the temporary search refcounting.

Finally, drop the redundant "root = NULL" before the second search loop. The
pci_get_class() iterator always decrements the refcount of its "from"
argument, so the first loop can only fall through with "root" already NULL.

Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching")
Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com
Reported-by: Sashiko <sashiko-bot@kernel.org>
Assisted-by: LLM
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Cc: <stable@kernel.org>
Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com

1 files changed, 56 insertions, 0 deletions

diff --git a/fs/lockd/nlm.h b/fs/lockd/nlm.h
new file mode 100644
index 000000000..47be65d01
--- /dev/null
+++ b/fs/lockd/nlm.h
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Declarations for the Network Lock Manager protocol.
+ *
+ * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
+ */
+
+#ifndef _LOCKD_NLM_H
+#define _LOCKD_NLM_H
+
+
+/* Maximum file offset in file_lock.fl_end */
+# define NLM_OFFSET_MAX		((s32) 0x7fffffff)
+# define NLM4_OFFSET_MAX	((s64) ((~(u64)0) >> 1))
+
+/* Return states for NLM */
+enum {
+	NLM_LCK_GRANTED			= 0,
+	NLM_LCK_DENIED			= 1,
+	NLM_LCK_DENIED_NOLOCKS		= 2,
+	NLM_LCK_BLOCKED			= 3,
+	NLM_LCK_DENIED_GRACE_PERIOD	= 4,
+#ifdef CONFIG_LOCKD_V4
+	NLM_DEADLCK			= 5,
+	NLM_ROFS			= 6,
+	NLM_STALE_FH			= 7,
+	NLM_FBIG			= 8,
+	NLM_FAILED			= 9,
+#endif
+};
+
+#define NLM_PROGRAM		100021
+
+#define NLMPROC_NULL		0
+#define NLMPROC_TEST		1
+#define NLMPROC_LOCK		2
+#define NLMPROC_CANCEL		3
+#define NLMPROC_UNLOCK		4
+#define NLMPROC_GRANTED		5
+#define NLMPROC_TEST_MSG	6
+#define NLMPROC_LOCK_MSG	7
+#define NLMPROC_CANCEL_MSG	8
+#define NLMPROC_UNLOCK_MSG	9
+#define NLMPROC_GRANTED_MSG	10
+#define NLMPROC_TEST_RES	11
+#define NLMPROC_LOCK_RES	12
+#define NLMPROC_CANCEL_RES	13
+#define NLMPROC_UNLOCK_RES	14
+#define NLMPROC_GRANTED_RES	15
+#define NLMPROC_NSM_NOTIFY	16		/* statd callback */
+#define NLMPROC_SHARE		20
+#define NLMPROC_UNSHARE		21
+#define NLMPROC_NM_LOCK		22
+#define NLMPROC_FREE_ALL	23
+
+#endif /* _LOCKD_NLM_H */